docs: :memo: configure louie

[vaimdevs]

Configure louie with databricks connector. We can use env var or nexus api for databricks configuration

[lmeyerov]

We should probably split connector discussion by secret management lifecycle:

Sections:

• Key concepts
• Initial env setup: key generation & sharing, system restarts, ...
• Adding a connector
• Service account: Adding, updating, removing
• User PAT table: Creating, inspecting, updating all/individual, deleting all/individual

Internal instructions: How to do without a Graphistry upgrade

For now, assume only self-hosted Graphistry+Louie (seperate nodes)